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Starting anew: Part II of a Reporter series on marsh ecosystems


AMBROSE CLANCY PHOTO Dickerson Creek, where it begins to flow into an endangered salt marsh.
AMBROSE CLANCY PHOTO Dickerson Creek, where it begins to flow into an endangered salt marsh.

Under a reef of cloud sailing slowly east, Dickerson Creek sparkles with May sunlight. The saltwater estuary streams out of the depths toward land, pooling in borders of peat, reeking pleasantly of salt and earth.

From the pools the current slowly continues over flooded mudflats. An egret, pure white, standing on stick legs in blue water, jerks forward, freezes — posing. Look closely and below the surface tiny creatures spring and dart from narrow burrows in the black mud.

The stream is gently funneled into a culvert that runs under Midway Road and once through, emerges into a night-and-day landscape. What was a salt marsh teeming with life for centuries, even after the road was made and the culvert underneath designed to feed it, is now limping along, disappearing in brush and tangled vines.

Until last week, when the Highway Department unclogged the culvert feeding the other side of Midway Road, the salt marsh, which is on town-owned land, was as good as dead. With water from Dickerson Creek now filtering through, the marsh is a patient on life support. There’s hope, which might not be enough, for a life source that has thrived down the decades on the south side of Shelter Island.

What’s gone wrong?
Allowing salt marshes to dry into mudflats is breaking a natural chain, according to Island environmentalist and member of the Green Options Advisory Committee, Herb Stelljes.

“It’s incremental damage,” he said. “The whole food chain is jeopardized,” affecting fish, herons, egrets, plant life and will open the way for invasive species to flourish.

What’s needed to sustain the ecosystem is a variety of life providing stability as various species feed off others.

Ignoring the ecosystem is similar to purchasing items with a credit card, Mr. Stelljes said. Sooner or later the debt comes due and ignoring environmental needs is building up a debt with all kinds of hidden costs.

“When do we face the issue,” he asked, adding that he’s witnessed a decline in the ecosystem in the 30 years he has lived on Shelter Island.

At the top of his list for getting ahead of the situation would be hiring a summer intern who could scour Shelter Island for incidences of threatened salt marshes and other environmental lapses.

“Jay can’t be everywhere,” Mr. Stelljes said, referring to Public Works Commissioner Jay Card Jr.

Mr. Card admitted that while he had seen a pothole on the roadway at Dickerson Creek, he hadn’t realized the water that typically flows from Dickerson Creek into the salt marsh was blocked. A resident informed him of the problem and a temporary solution is in place. But a permanent solution will cost in excess of $7,500 ­— money he can’t find in his budget.

As for the salt marsh at Hay Beach, Mr. Card was aware of the problem and already exploring solutions that would allow water to run through the marsh as freely as it once did. Since dredging took place at the foot of Hiberry Lane, water will have to run uphill in order to flow through, to refresh what had long been a healthy salt marsh.

What’s the solution?
Shelter Island isn’t alone in seeing salt water marshes and the life they grow and protect being extinguished.

As the Island chooses to confront, or ignore, salt marshes in peril at Hay Beach and Dickerson Creek, restoration actions are underway in Rhode Island and on Cape Cod that are models for other communities. Not far from here, the Narragansett Bay Reverse Trends Analysis Project is confronting the issue, as is the Association for the Preservation of Cape Cod.

“Since colonial times, a significant portion of our nation’s salt marshes have been degraded or altered by agriculture, mosquito-ditching, channeling, urban development and other legacies of human activities,” according to a report compiled by the Cape Cod group.

The result is fewer species inhabiting the area, replaced by invasive species such as phragmites that thrive in brackish water. Closer to home in East Marion, residents spent several years removing phragmites from their water and planting native species that thrive in healthy salt marshes. That project was undertaken by neighbors without help from the town of Southold.

Cape Cod has also depended on volunteers to observe and report changes that can be documented to focus the attention of officials on the need for restoration.

In Rhode Island, the effort is more action driven, bringing together the Rhode Island Department of Environmental Management’s Narragansett Bay Estuary Program, the University of Rhode Island Environmental Data Center, the U.S. Fish and Wildlife Service and the University of Massachusetts Natural Resource Assessment Group.

How to start
The project is concentrated on both restoration of endangered salt marshes and the creation of new ones.

But as with all such efforts, money is a factor and it’s why the first advice that comes from the group is to prioritize potential salt marsh restoration sites.

“It is essential that the site selection process generates a list of alternatives that offer the best chance of achieving the greatest output,” according to a report, “Restoring Coastal Habitats for Rhode Island’s Future” from the University of Rhode Island.

Money for the environmental projects is solicited from a number of sources — federal, state and private funding. An online database called “Habitat Restoration Projects: A Citizens Guide” provides a guide to those seeking to get involved in restoration projects, according to the Rhode Island group.

The Narragansett Bay Estuary Program is developing a Geographic Information Systems database with maps showing locations of potential restoration sites. It will include information on the critical habitat resources at each site along with socioeconomic data.

Among the data important in determining the best sites for restoration — and a project ideal for an intern to take on — are:

•    Identification of invasive plant species
•    History of dredging operations with information on materials or fill placements
•    Hydrologic restrictions
•    Ownership of adjacent properties
•    Regulatory considerations

Environmentalists in Salem, Massachusetts use a seven-point scale to assess the health of Salem’s wetlands in order to identify areas in need of remediation. They include the presence and types of fish; aquatic macro invertebrates; plant diversity; salinity of small groundwater wells; tidal influences; land use; and bird populations that are a good bioindicator of the health of salt marshes, according to Salem Sound Coastwatch.

Artificial future?
With historic drought conditions in California, residents in states on both coasts are watching and waiting to see how that state responds. The California Institute for Biodiversity notes that coastal salt marsh habitats are rare on the Pacific Coast because of cliffs and rocks, rather than mudflats. California’s salt marshes represent only three percent of such formations in the entire United States.

Still, they are recognized for their ability to filter out pollutants, and there are moves toward restoration and creation of artificial marshes, with projects in San Francisco Bay, the Sonoma Baylands, near Santa Barbara, and in San Diego Bay, among others.

While there has been some success, none of the efforts has been able to imitate natural marshes, according to the institute’s report.

“Much work is being done to figure out how to make artificial marshes function more like natural ones,” the report said.

But Atlantic coastal communities don’t need imitation salt marshes, if the ones that have been here for thousands of years can be restored and protected.


AMBROSE CLANCY PHOTO The marsh, on town-owned land, fed by Dickerson Creek.

AMBROSE CLANCY PHOTO The marsh, on town-owned land, fed by Dickerson Creek.

The salt marsh is a complex environment where land habitats begin to interact with the sea.

The marsh provides a variety of conditions for many life forms, including millions of microscopic organisms. Directly or indirectly, the salt marsh and its related estuaries are the ultimate hatchery and nursery, eventually providing food and nutrients for much of the sea life we are familiar with. This is where it all begins.

Once commonly considered to be of little value, these areas were dredged and filled in. One by one, these productive biological zones (more productive than a typical cornfield in the Midwest) were destroyed.

Some of the supply shortages we now face, such as the loss of a reliable scallop population, decline in lobsters, crabs and many oceanic fish species, can be linked, at least in part, to devastation done to our endangered salt marsh and estuary.

Biologists describe the interactions of ecosystems in salt marshes in terms of energy flow through food chains.  A simplified version might start with microscopic algae, ingested as food by an oyster, scallop or clam, which in turn may be eaten by any combination of snails, crabs, worms, bacteria, or perhaps by some of us at a cookout.

Small fish are born in the marsh-estuary complex, get bigger and become food for a diving tern, perhaps a stalking egret, blue heron or bigger fish. They may also be caught by people to be used as bait and find their way into the ocean ecosystem, only to return to land in a fish market, or as dinner on our plate at a restaurant on Shelter Island.

But many things can upset the natural balance.  Here on the Island, excess nitrogen from inadequate septic systems or too much fertilizer on our green lawns works its way into our estuaries and is contributing to a nutrient overload in our waterways. The erratic shift in the scallop population is often cited as one such negative consequence.

Pesticides and herbicides certainly don’t help either, often destroying the critical larval stage of many species before they have a chance to reproduce and thrive.

Destruction of salt marshes, either planned or by benign neglect, exists here and beyond our shores, with consequences that can only be termed dire.